For such machines, the stalks of the harvested crops are drawn in the upright position by feeding and mowing drums and mown and subsequently supplied to the chopper by means of insertion rollers, with which the chopper is connected in series. All feeding and mowing drums are driven by one driving unit, which can be connected to the central power train of the chopper, which usually is self-propelled. In the course of the rationalization of the harvesting operation, large self-propelled up to 500 HP field choppers are used. Correspondingly large driving power is transferred to the feeding and mowing drums, of which two, three or more may be disposed on either side of the vertical, longitudinal median plane of the machine.
The propulsion of these combined feeding and mowing drums when the machine is started for harvesting operation turns out to be difficult owing to the fact that the masses, which are to be set in rotary motion, are very high. As a result, a high torque is required during the starting-up phase, in order to set the feeding and mowing drums of the machine in rotary motion with the required operating speed. A construction of the driving unit with two individual shaftings on either side of the vertical, longitudinal median plane of the machine, each driving a group of feeding and mowing drums, also basically does not lead to more advantageous conditions with respect to the starting-up behavior of the feeding and mowing drums, if the high starting-up torques are to be transferred simultaneously to all feeding and mowing drums of the machine over the central power train of the chopper.
It is an object of the invention to improve the starting-up conditions for the harvesting operation of machines of the given type.